Top quilt over the head...WOW!!

**OneClick** · 03-30-2015, 08:46

After camping for a good 15 years now, one of the top 3 "carved in stone" rules was to NEVER sleep inside your sleeping bag (top quilt). Condensation would just saturate your bag and clothes all night.

Well, for some reason this past weekend I couldn't resist. It was about 24° when I settled in and dropping to 18°. Not too cold, but with a slight breeze, no tarp doors and a very bright moon straight overhead, I knew it would be difficult.

I'm not sure why, but my face just felt colder than usual. In the winter I can sleep at 5° with just a hat, but not in this warmer weather for some reason.

So I pulled my 20° Burrow over my head and tucked it around so it was completely sealed. I'm 69" tall and the Burrow is 74", so it worked fine. I think I was out within minutes, planning on waking up in an hour to find a soggy, damp quilt. Instead, I only woke up once to pee after 5 hours. Everything was completely dry and fine. When I woke up for good several hours later, everything was still fine.

The next night I tried it again figuring it was a fluke, due to dry air, dewpoint, breeze, something. Well, same thing as the first night. Everything was dry, very comfortable and extremely warm. It was like sleeping indoors!! At one point, I was a little warm so I made a hole to vent around my face. Of course, this caused some condensation on the quilt. I wiped it dry and went back to bed under the quilt. Back to a perfect sleep until sunrise.

So then I started thinking, this makes sense. I was completely enclosed so my body, head, face and everything created a mini "environment", probably above 70°...so no condensation could form.

I may have to try this in the winter to see what happens. But if it worked this well at 18°, I'm really excited to know it is possible to do without getting everything damp. I think I remember this being mentioned, and it may have been Dutch using a quilt over the head.

**locknload** · 03-30-2015, 08:56

I've done this with a down sleeping bag. I'm a cold sleeper so I have to tuck all the way in. One trip it was in the mid twenties and another was in the mid teens. I too had to vent here and there by sticking my face out for a bit. No condensation those times.

**Brewguy** · 03-30-2015, 11:08

isn't the risk condensation inside the insulation? Your moisture does go into the bag but does it come out the other side or freeze to the outer layer?

leaving the vent hole should prevent that problem.

**OneClick** · 03-30-2015, 11:18

Originally Posted by Brewguy

isn't the risk condensation inside the insulation? Your moisture does go into the bag but does it come out the other side or freeze to the outer layer?

leaving the vent hole should prevent that problem.

That's the risk, and also the point I was making since there was absolutely no sign of it anywhere. It's when you vent, you get cold air mixing - when your warm moist breath hits that, you get condensation on the quilt all around your mouth. Under the quilt, everything is warm so no condensation is not going to form. I didn't see or feel anything on the outer layer.

I always weight my quilts before and after out of habit to try and find evidence of moisture in general. I did not see any difference. It was in a stuff sack for a few hours hiking and 3hr drive home, but I doubt it could have dried much if any.

**altruistguy** · 03-30-2015, 12:09

Hello Mark,

Am glad that you were comfy. If I were you, I would only do this on overnight "backyard-" type adventures. That vapor from your breath had to go somewhere. The only possible place for it to go (if it isn't on you) is inside the TQ's insulation. Regardless of what (you believe that) your weigh-ins prove, it simply must be the case that the vapor is inside your insulation. Perhaps your weighing scale isn't as accurate as you thinK?

I'd hate to do this on a week-long backpacking adventure, for example. If not concerned about the accumulating water weight in the insulation, I'd be concerned about decreasing insulating ability and accumulating/accelerating down bunching and bacterial growth inside the insulation.

But then again, if you were using a synthetic TQ, I'd say to have fun -- trying whatever works. For me, I wouldn't want to damage my precious down. And I wouldn't want the accumumulating water to decrease thermal insulating ability if it is truly cold at night.

**OneClick** · 03-30-2015, 12:18

If the entire inside of this quilt was (60, 70, 80°?), then wouldn't I get the same condensation in my bedroom every night? I know there is no cold air to speak of in that situation, but if the quilt is doing it's job at keeping the heat in, why should there be any concern about the cold air outside of it? If my breath is warm and the air all around is warm, I don't see (and didn't see) any issue with condensation forming. Now if it was 1/2" of down, I could maybe see the warm/cold layers being too close together NOT to have condensations. But were talking 2+" of loft here.

2 cold nights was enough proof for me, but I will still use caution next time and give it a good test come fall. Actually, I'm doing a kayaking trip at Negwegon on Lake Huron early May...could be warm, could be cold. I may give it another try then.

p.s. One more thing. Not that this proves anything either, but usually in the winter I will put my head under the covers for a minute while checking the weather on my phone (just to keep my hands warm while holding it up). I notice immediately the screen gets foggy with one breath and continues to get worse since I'm not totally "sealed in". But this time, I actually watched about 10 minutes of a movie just for fun and didn't see anything on the screen. Even after breathing pretty much right on it.

**brokentree** · 03-30-2015, 12:25

Related: http://scorpioart.com/malaysia/wp-co...9HggYgx_ph.jpg

**OneClick** · 03-30-2015, 12:29

Originally Posted by brokentree

Related: http://scorpioart.com/malaysia/wp-co...9HggYgx_ph.jpg

LOL! I've actually dreamed up some contraptions like this in the past to avoid a damp sleeping bag around my face in the winter!

**Brewguy** · 03-30-2015, 12:59

while the inside of your tq is 70 degrees the outside might be 20, somewhere in the middle, certainly at the outer fabric the temp is close to the outside temp. At that point the condensation forms.

The question is if its enough to be a problem and how many days before it is a problem. You probably can't measure the moisture, its probably just a few drops in total. It might not ever be a problem, maybe after 2 or 3 weeks?

**tundracamper** · 03-30-2015, 13:02

So I guess the question has to do with the dew point inside the quilt. Inside the quilt layer, the temperature drops from 70F inside to around 20F outside. That means at some location inside the quilt that the temperature drops to the dew point, where condensation occurs. Is there enough moisture inside the quilt at that point to cause condensation? Or, does the down and inside barrier prevent that much moisture from permeating through the down?

Either way, I'd be prone to stick the quilt in the dryer.